Concentration and characterization of microplastics in Blue mussels (Mytilus edulis) and Eastern oysters (Crassostrea virginica) from Nova Scotia

Abstract

Microplastics (MPs) (<5 mm) have become an increasingly global concern due to their potential to impact both human health and the environment. This research explored the occurrence of microplastics in Blue mussels (Mytilus edulis) and Eastern oysters (Crassostrea virginica) from three fishing regions across Nova Scotia, Canada. This study also explored common and emerging methods for microplastic research in marine mussel and oyster species. Results found evidence of plastic in both bivalves. Average suspected microplastic (SMP) concentration was 4.25 ± 1.48 SMPs/g of wet weight (ww) tissue and 3.79 ± 1.27 SMPs/g of ww tissue in mussels and oysters, respectively. The average MP size classification was 2-10 µm and 10-20 µm for mussels and oysters, respectively. Results found that factors such as sampling location and species of bivalve influenced SMP concentrations. Plastic polymers were identified in bivalves including, polyethylene (PE), polyvinyl chloride (PVC), and polypropylene (PP). Potential sources include marine shellfish aquaculture equipment, packaging, and other land-based plastics. Results found trends in the research of MPs in bivalves and noted future considerations such as the use of temperature in processing and storage, as well as methods for analyzing small size MPs. The findings from this study highlight the need for standardized methods in MP research and further monitoring for MPs in shellfish farmed or caught for human consumption.